Tip deformities as small as 10 mum on cannulae can cause unnecessary pain to patients. The only way of preventing these deformed cannulae from reaching patients is to test every cannula at the manufacturing stage. Clinical and laboratory tests carried out by the company compare handling and trauma caused by medical cannulae with technical parameters for manufacturing and testing. This article discusses the results of these tests, which the author found verified that the properties of medical cannulae can be evaluated by measuring the penetration load piercing a skin substitute. The discovery of tip deformities with clinical significance led to the development of specially designed equipment that detects the presence of deformities by using the noise made by a deformed cannula penetrating a foil.